P38A Immobiliser removel

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
Grrrrrr said:
Calibration block dimensions are in Wammers post in the Technical Section, I think. Easy job. I'd split the difference across each axle as it doesn't make that much difference as long as they're within expected ranges.
Click to expand...
thanks.
i'll have a read later and hopefully have a go at sorting it at the weekend
 
If you've got a digital volt meter you could check the output from each height sensor and make sure it varies smoothly across the range of movement. Open tailgate to disable suspension and make sure you have axle-stands under the chassis.
 
Grrrrrr said:
To fix it? Wrote the correct EMS code to the BECM. Only thing I know that works.
Click to expand...

So the ECM/BECM had gone out of sync then and the number in the BECM was scrambled. That would not be caused by the locks but by a flat battery trying to start the engine. If the locks have a problem (lack of RF signal) on your year of car the BECM would not switch the ECM on, and the EKA code would be required to sort that.. That is why passive immobilisation was introduced in 1997. As said with ECM/BECM out of sync there is no dash message either on your year or any other year of car. On later models the starter circuit is disabled to prevent the battery being flattened trying to start the car and so prevent sync problems.
 
wammers said:
So the ECM/BECM had gone out of sync then and the number in the BECM was scrambled. That would not be caused by the locks but by a flat battery trying to start the engine. If the locks have a problem (lack of RF signal) on your year of car the BECM would not switch the ECM on, and the EKA code would be required to sort that.. That is why passive immobilisation was introduced in 1997. As said with ECM/BECM out of sync there is no dash message either on your year or any other year of car. On later models the starter circuit is disabled to prevent the battery being flattened trying to start the car and so prevent sync problems.
Click to expand...

I understand what you're saying and agree but just relating what occurred.

No battery problems. It was new at the time. I drove down, resynced the engine for her and she started up and drove home. Did it a few times. TFFT Nanocom. Fitted the upgraded RF receiver and no more issues. I disabled passive immobilisation at some point too. I've left the EKA enabled but cannot recall ever using it. EKA issues seem to be related to ignition barrel sticking and microswitches on door acting up when using the key from the experience on the scrapper.
 
Grrrrrr said:
I understand what you're saying and agree but just relating what occurred.

No battery problems. It was new at the time. I drove down, resynced the engine for her and she started up and drove home. Did it a few times. TFFT Nanocom. Fitted the upgraded RF receiver and no more issues. I disabled passive immobilisation at some point too. I've left the EKA enabled but cannot recall ever using it. EKA issues seem to be related to ignition barrel sticking and microswitches on door acting up when using the key from the experience on the scrapper.
Click to expand...

1995 DTs don't have passive immobilisation.
 
Datatek said:
The engine does get immobilised though when the ignition is turned off so it helps to turn off the immobiliser.
Click to expand...

How can you turn something off that's not fitted? When the engine is switched off the ECU cuts power to the quantity servo, which drops to zero fuel, stopping the engine, the fuel cut off solenoid also drops but that does not stop the engine, that is just an emergency back up if a fault is detected whilst the engine is running. If for instance if quantity feedback to ECU is lost the stop solenoid will drop to stop the engine. Passive immobilisation was only introduced for MY 1997 his car does not have it, so disabling it does nothing. You can disable passive immobilisation (If fitted). But you cannot disable ECM to BECM immobilisation.;)
 
wammers said:
How can you turn something off that's not fitted? When the engine is switched off the ECU cuts power to the quantity servo, which drops to zero fuel, stopping the engine, the fuel cut off solenoid also drops but that does not stop the engine, that is just an emergency back up if a fault is detected whilst the engine is running. If for instance if quantity feedback to ECU is lost the stop solenoid will drop to stop the engine. Passive immobilisation was only introduced for MY 1997 his car does not have it, so disabling it does nothing. You can disable passive immobilisation (If fitted). But you cannot disable ECM to BECM immobilisation.;)
Click to expand...
I think you are confusing what the coil on the ignition barrel actually does, it forces he FOB to send the rolling code, nothing directly to do with actual immobilisation of the engine which relates to the need for the BECM to send a code to the EDC that matches the pre-written code held in the EDC in order for the EDC to be enabled letting the engine start. The immobiliser flag is there on all the BECM's i've seen regardless of the presence of the of the so called passive coil which itself is not passive but active with i's own built in oscillator circuit switched by the BECM, the coil is turned off with the Immobilser flag.. It is not possible to disable the BECM to EDC immobiliser code, turning off the immobiliser flag alters the the prompt for the BECM to send the required code to the EDC and as far as I can see applies to all versions regardless of the passive coil. In effect the BECM to EDC code transfer becomes automatic with no need for the FOB or EKA code if EKA is also turned off or anything else for that matter
 
Datatek said:
I think you are confusing what the coil on the ignition barrel actually does, it forces he FOB to send the rolling code, nothing directly to do with actual immobilisation of the engine which relates to the need for the BECM to send a code to the EDC that matches the pre-written code held in the EDC in order for the EDC to be enabled letting the engine start. The immobiliser flag is there on all the BECM's i've seen regardless of the presence of the of the so called passive coil which itself is not passive but active with i's own built in oscillator circuit switched by the BECM, the coil is turned off with the Immobilser flag.. It is not possible to disable the BECM to EDC immobiliser code, turning off the immobiliser flag alters the the prompt for the BECM to send the required code to the EDC and as far as I can see applies to all versions regardless of the passive coil. In effect the BECM to EDC code transfer becomes automatic with no need for the FOB or EKA code if EKA is also turned off or anything else for that matter
Click to expand...

I am confusing nothing i know exactly what the passive coil does. But it can't do if if there isn't one fitted as in Grrrrrrs case. Grrrrrr said his ECM/BECM lost sync because of faulty RF receiver and he had to resync them. The only way i can think of to cause that to happen is if the RF memory becomes full unable to accept any more inputs and the BECM loses it's marbles, i don't know. But RF memory is deletable. It is an enigma. Even if passive is fitted and no message is visible the ECM/BECM sync can be lost in some cases. And there is no indication of that other than the engine will turn for ever and not start. That is why BBS made a fortune selling Syncmates.
 
You must log in or register to reply here.

Similar threads

rangie1998
L322 Front doors deadlocked, do I have to break the locks?
Replies
1
Views
542
rangie1998
rangie1998
I
L322 Range Rover 2005 - rear doors, tailgate, fuel cap locked
Replies
1
Views
588
pwood999
pwood999
Beretta man
Discovery new fob
Replies
6
Views
839
sierrafery
sierrafery
tarphenry
p38 diesel
Replies
15
Views
732
tarphenry
tarphenry
kermit_rr
L322 keyfob signal not received
3 4 5
Replies
93
Views
3K
kermit_rr
kermit_rr
Back
Top